#ifndef UART_H
#define UART_H

#include "main.h"
/*
** constants and macros
*/

/** @brief  UART Baudrate Expression
 *  @param  xtalcpu  system clock in Mhz, e.g. 4000000L for 4Mhz
 *  @param  baudrate baudrate in bps, e.g. 1200, 2400, 9600
 */
#define UART_BAUD_SELECT(baudRate,xtalCpu) ((xtalCpu)/((baudRate)*16l)-1)

/** @brief  UART Baudrate Expression for ATmega double speed mode
 *  @param  xtalcpu  system clock in Mhz, e.g. 4000000L for 4Mhz
 *  @param  baudrate baudrate in bps, e.g. 1200, 2400, 9600
 */
#define UART_BAUD_SELECT_DOUBLE_SPEED(baudRate,xtalCpu) (((xtalCpu)/((baudRate)*8l)-1)|0x8000)


/** Size of the circular receive buffer, must be power of 2 */
#ifndef UART_RX_BUFFER_SIZE
#define UART_RX_BUFFER_SIZE 128
#endif
/** Size of the circular transmit buffer, must be power of 2 */
#ifndef UART_TX_BUFFER_SIZE
#define UART_TX_BUFFER_SIZE 128
#endif

/*
** high byte error return code of uart_getc()
*/
#define UART_FRAME_ERROR      0x0800              /* Framing Error by UART       */
#define UART_OVERRUN_ERROR    0x0400              /* Overrun condition by UART   */
#define UART_BUFFER_OVERFLOW  0x0200              /* receive ringbuffer overflow */
#define UART_NO_DATA          0x0100              /* no receive data available   */


/*
** function prototypes
*/

/**
   @brief   Initialize UART and set baudrate
   @param   baudrate Specify baudrate using macro UART_BAUD_SELECT()
   @return  none
*/
extern void uart_init(unsigned int baudrate);


/**
 *  @brief   Get received byte from ringbuffer
 *
 * Returns in the lower byte the received character and in the
 * higher byte the last receive error.
 * UART_NO_DATA is returned when no data is available.
 *
 *  @param   void
 *  @return  lower byte:  received byte from ringbuffer
 *  @return  higher byte: last receive status
 *           - \b 0 successfully received data from UART
 *           - \b UART_NO_DATA
 *             <br>no receive data available
 *           - \b UART_BUFFER_OVERFLOW
 *             <br>Receive ringbuffer overflow.
 *             We are not reading the receive buffer fast enough,
 *             one or more received character have been dropped
 *           - \b UART_OVERRUN_ERROR
 *             <br>Overrun condition by UART.
 *             A character already present in the UART UDR register was
 *             not read by the interrupt handler before the next character arrived,
 *             one or more received characters have been dropped.
 *           - \b UART_FRAME_ERROR
 *             <br>Framing Error by UART
 */
extern unsigned int uart_getc(void);


/**
 *  @brief   Put byte to ringbuffer for transmitting via UART
 *  @param   data byte to be transmitted
 *  @return  none
 */
extern void uart_putc(unsigned char data);


/**
 *  @brief   Put string to ringbuffer for transmitting via UART
 *
 *  The string is buffered by the uart library in a circular buffer
 *  and one character at a time is transmitted to the UART using interrupts.
 *  Blocks if it can not write the whole string into the circular buffer.
 *
 *  @param   s string to be transmitted
 *  @return  none
 */
extern void uart_puts(const char *s );


/**
 * @brief    Put string from program memory to ringbuffer for transmitting via UART.
 *
 * The string is buffered by the uart library in a circular buffer
 * and one character at a time is transmitted to the UART using interrupts.
 * Blocks if it can not write the whole string into the circular buffer.
 *
 * @param    s program memory string to be transmitted
 * @return   none
 * @see      uart_puts_P
 */
extern void uart_puts_p(const char *s );

/**
 * @brief    Macro to automatically put a string constant into program memory
 */
#define uart_puts_P(__s)       uart_puts_p(PSTR(__s))

/**
 * @brief    Put nibble as hex to ringbuffer for transmit via UART.
 *
 * The lower nibble of the parameter is convertet to correspondig
 * hex-char and put in a circular buffer and one character at a time
 * is transmitted to the UART using interrupts.
 *
 * @param    value to transfer (byte, only lower nibble converted)
 * @return   none
 * @see      uart_putc
 */
extern void uart_puthex_nibble( const unsigned char b );

/**
 * @brief    Put byte as hex to ringbuffer for transmit via UART.
 *
 * The upper and lower nibble of the parameter are convertet to
 * correspondig hex-chars and put in a circular buffer and one
 * character at a time is transmitted to the UART using interrupts.
 *
 * @param    value to transfer
 * @return   none
 * @see      uart_puthex_nibble
 */
extern void uart_puthex_byte( const unsigned char b );


extern void uart_puthex_16byte( const uint16_t lbyte );
/**
 * @brief    Put unsigned long as ASCII to ringbuffer for transmit via UART.
 *
 * @param    value to transfer
 * @return   none
 * @see      none
 */
extern void uart_puthex_long( unsigned long l );

/*
** Defined Functions
*/


#define uart_clr() uart_putc((char)2); _delay_ms(10); uart_puts_P("\n\r"); _delay_ms(200)



#endif // UART_H

